Many applications require the temporary securing of a flexible sheet of material to a rotatable drum. Apparatus such as electrostatic copiers and facsimile machines, for example, often employ a drum-type mechanism for supporting a sheet of paper or film during reading and writing processes.
U.S. Pat. No. 4,033,575 to Fujimoto shows one type of automatic sheet feed and delivery apparatus employing a rotatable drum for supporting the sheet. Fujimoto includes leading and trailing edge clamps for securing the sheet to the drum, and a variety of complex, movable, rotatable cam and lever mechanisms for controlling these clamps. The apparatus shown in the Fujimoto patent suffers from the disadvantage of being extremely complex in construction and operation.